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With Locke's goal-setting theory, he believes the best way to motivate an employee is to set and manage task goals. Adams' equity theory is a comparison of inputs and outputs of employees amongst other employees. These both can be incorporated into Vroom's expectancy theory which states for motivation to be present you will need expectancy, instrumentality and value of an employee.
If you are using Locke's goal-setting theory you need to ensure managers and leaders work with the employees to set the right goals with the most proper path to completion. This can be incorporated into Vroom's expectancy theory because communicating is the main factor with Locke's, and communicating is the best way to ensure Vroom's theory works. In order for Vroom's theory to thrive you need communication and understanding between managers and employees or it will fail. You need to know your employees value, know the best way for the specific employee to achieve success with the task at hand reward employees in ways they will appreciate most. Using some concepts from Locke's theory could improve Vroom's theory dramatically. If any of the three factors are missing with Vroom's theory it will not work and there will be no motivation. However, if a manager sets goals with an employee all three factors should be present and powerful. Accomplishing goals will show an employee that hard work pays off. If you accomplish a goal you set, the end result is a desirable outcome. Setting goals with a manager will give the employee a chance to explain to him what his/her values are. With this being said, all three of Vroom's factors are present using ideas from Locke's goal-setting theory.
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